Lysozyme-sensitive variants belonging to genus Corynebacterium are used for the manufacture of glutamic acid (Examined Published Japanese Patent Application (JP-B) No. Hei 1-29555) and of glutamine (JP-B Sho 62-49038) and are also used as hosts for the preparation of transformants (Unexamined Published Japanese Patent Application (JP-A) No. Sho 58-56678).
Microorganisms belonging to the genus Corynebacterium and having a sensitivity to lysozyme have been prepared by random introduction of mutation into a chromosome with a mutagenizing agent, followed by a selection of lysozyme-sensitive mutant(s) from the resulting strains (JP-B Sho 62-49038 and Hei 1-29555 and JP-A Sho 58-56678). According to such a method, however, in addition to the mutation concerning the lysozyme sensitivity, unfavorable mutation can also be accompanied therewith and, therefore, it is difficult to obtain a desired lysozyme-sensitive microorganism efficiently.